A radio equipment such as a base station and a user terminal in a radio communication system includes a power amplifier (hereinafter, sometimes referred to as “PA”) for amplifying a power of a transmission signal. In such radio equipment, the PA is operated near a saturation region of the PA in order to increase the power efficiency of the PA. However, when the PA is operated near the saturation region, a nonlinear distortion increases. Thus, in order to reduce an adjacent channel leakage power (ACP) by suppressing the nonlinear distortion in the PA, the radio equipment is provided with a distortion compensator that compensates the nonlinear distortion in the PA.
Related technologies are disclosed in, for example, Japanese Laid-Open Patent Publication Nos. 2006-121408 and 2006-270638.